As I wrote in the previous post, there might a situation when another/former load source disk become part of the LPAR configuration. IBMi OS configuration allows to run only with one valid load source, therefore the operating system will change a specific sector, making a former load source disk a regular disk. Therefore, this disk can’t be used as the Load Source never again. In this post I will describe what sector need to be changed in order to recover the disk, and reuse it in another configuration.
IBMi.org - Bart's blog 